The present invention relates to an ink jet recording head for use in an ink-jet printer, and particularly to an ink jet recording head in which an ink material is pressurized by a vibration of an actuator and then ejected.
There has been proposed an ink-jet recording head which comprises a head body having a recess and a nozzle fluidly communicated with the recess, a diaphragm covering the recess to form an ink cavity with the head body for receiving an ink material, and a piezo-electric actuator arranged adjacent the diaphragm to oppose the ink cavity. Typically, in this ink-jet recording head, the diaphragm is bonded by an adhesive, and the piezo-electric actuator is fixed in contact with or slightly spaced away from the diaphragm. In operation of the ink-jet recording head, the piezo-electric actuator is vibrated and the vibration is transmitted to the diaphragm, thereby the ink material is pressurized and thus ejected through the nozzle into the atmosphere.
The ink-jet recording head is effective for ejecting the ink material, but has a serious problem that a deformation energy of the piezo-electric actuator is not fully transmitted to the ink material due to a pressure loss at the diaphragm, thereby decreasing a force for ink ejection. Specifically, initially the diaphragm is well tensioned and therefore the vibration of the piezo-electric actuator is fully transmitted to the ink material through the diaphragm, however, the diaphragm deteriorates, or creeps, over time to lose its initial tension, which causes a pressure loss at the diaphragm or cracks in the diaphragm.